Many different technologies have been developed for fabricating switches and relays for low frequency and high frequency switching applications. Many of these technologies rely on solid, mechanical contacts that are alternatively actuated from one position to another to make and break electrical contact. Unfortunately, mechanical switches that rely on solid—solid contact are prone to wear and are subject to a condition referred to as “fretting.” Fretting refers to erosion that occurs at the points of contact on surfaces. Fretting of the contacts is likely to occur under load and in the presence of repeated relative surface motion. Fretting manifests as pits or grooves on the contact surfaces and results in the formation of debris that may lead to shorting of the switch or relay.
To minimize mechanical damage imparted to switch and relay contacts, switches and relays have been fabricated using liquid metals to wet the movable mechanical structures to prevent solid to solid contact. A typical switch uses mercury or gallium alloys to wet the contacts to reduce problems associated with solid—solid metal contact. Unfortunately, it has been difficult to design, fabricate and commercialize a switch having sub-millimeter size and employing liquid metal in some capacity to prevent fretting and that can carry sufficient current.